This invention relates to a refill unit for removable attachment to a wiper blade superstructure. More particularly the refill unit is intended for attachment to any one of a number of wiper blade superstructures of different size or length. The invention also relates to a clip for the refill unit.
Certain wiper blade assemblies comprise a wiper blade superstructure having a set of claw members for enabling attachment thereto of a wiper blade unit including an elongate flexible backing strip and an elongate resilient wiping element received in an elongate slot of the backing strip. Some such wiper blade units are designed for a specific size of wiper blade superstructure. For example often the distance between the endmost claw members at opposite ends of the wiper blade superstructure is only slightly less than the length of the backing strip. In such cases, the wiper blade unit normally includes an end clip which is detachably secured to one end of the backing strip to enable an endmost claw member to be releasably fastened to the end clip to resist sliding of the backing strip relative to the wiper blade superstructure. Examples of such wiper blade units are shown in Sharp U.S. Pat. No. 4,009,503, Sharp U.S. Pat. No. 4,156,951 and Thomson & Scotcher U.S. Pat. No. 4,360,943. Other such wiper blade units, however, are considerably longer than the distance between the two endmost claw members at opposite ends of the wiper blade superstructure and in such cases it is not feasible to use conventional end clips for releasably attaching the backing strip to one of the endmost claw members. Such wiper blade assemblies are referred to as "short frame" blade assemblies.
The wiper blade superstructures of known short frame blade assemblies are produced in different sizes. It is known to provide a single length refill unit for use with a number of different size wiper blade superstructures. Such known refill units generally include a claw-engaging clip which is detachably securable at different positions along the length of the backing strip. Examples of such known refill units are shown in Kimber & Norris U.S. Pat. No. 4,388,742, Riester U.S. Pat. No. 4,389,747, Sharp U.S. Pat. No. 4,442,566, Plisky U.S. Pat. No. 4,501,043, Baerenwald, Mohnach & Plisky U.S. Pat. No. 4,566,147 and Will U.S. Pat. No. 4,583,259. Another known refill unit is shown in Kessler & Mayer U.S. Pat. No. 4,571,770 and employs an end clip with spacers positionable between the end clip and the endmost claw member. Although some of these known refill units disclose the use of resilient clips having engaging means engaging in selected ones of longitudinally spaced apart apertures formed in an elongate central portion of a backing strip, none of the engaging means are in the form of latching members which extend from resiliently deflectable spaced apart legs of the clip.